Traditional wireless networks include a number of base stations (BTSs) in one or more mobile switching centers (MSCs). The BTSs each cover a geographic region, or cell of the wireless network and communicate with mobile telephones in the cell over a wireless link. The MSCs provide switch and soft handoff functionality for the wireless network. The wireless link may be based on established standards such as IS-54 (TDMA), IS-95 (CDMA), GMS and AMPS, 802.11 based WLAN, new upcoming standards such as CDMA 2000 and W-CDMA or proprietary radio interfaces.
Wireless networks include macro networks covering large geographic regions and smaller wireless campus networks covering a specific structure such as an office building or a set of related structures such as a corporate campus within a defined area. Campus networks often overlay one or more macro networks and provide corporate and other subscribers with preferential rate or services as compared to the macro network. Accordingly, a mobile device subscribing to the campus network will when activated camp onto the macro network only when the device is outside the coverage area of the campus network or otherwise unable to camp onto the campus network.
During operation, as the mobile device roams, it scans and selects networks based on signal strength. This ensures maximum call quality and allows for efficient handoff between cell sites and wireless networks. However, no accounting is made for network preference in areas of overlapping coverage.